The 250-acre Edison facility -- which houses the EPA Region 2 Division of Science and Assessment, a national laboratory and other offices -- is purchasing power generated from biomass and landfill methane through Pepco Energy Services of Washington. The EPA uses about 4.5 million kilowatt-hours of electricity annually at the Edison facility.

Switching to renewable resources will reduce emissions of sulfur dioxide, which contributes to acid rain, and nitrogen oxides, which contribute to smog, according to the EPA.

Nationally, more than 10 percent of the EPA´s electricity comes from renewable sources.